using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Linq;
using System.Reactive;
using System.Text.RegularExpressions;
using MsBox.Avalonia;
using ReactiveUI;

namespace Prak12.ViewModels
{
	public class AddTeachersViewModel : ReactiveObject
	{
        public AddTeachersViewModel()
        {
            AddNewTeacherCommand = ReactiveCommand.Create<string>(AddNewTeacherCommandRun);
            CancelAddNewTeacherCommand = ReactiveCommand.Create<string>(CancelAddNewTeacherCommandRun);
            using (AvaloniaPrakt12DbContext DB = new AvaloniaPrakt12DbContext())
            {
                UnselectedSubjects = new ObservableCollection<Subject>(DB.Subjects.ToList());
            }
        }


        public event Action AddNewTeacherPageWasClosed;


        public Teacher Teacher
        {
            get => _teacher;
            set => this.RaiseAndSetIfChanged(ref _teacher, value);
        }

        public DateTimeOffset Date
        {
            get => _date;
            set => this.RaiseAndSetIfChanged(ref _date, value);
        }

        public int GenderComboboxId
        {
            get => _genderComboboxId;
            set => this.RaiseAndSetIfChanged(ref _genderComboboxId, value);
        }
        public string TeacherWorkTime
        {
            get => _teacherWorkTime;
            set => this.RaiseAndSetIfChanged(ref _teacherWorkTime, value);
        }
        public int SelectedComboBoxSubjectId
        {
            get => _selectedComboBoxSubjectId;
            set
            {
                this.RaiseAndSetIfChanged(ref _selectedComboBoxSubjectId, value);
                if (value != -1)
                {
                    _selectedSubjects.Add(UnselectedSubjects[value]);
                    _unselectedSubjects.RemoveAt(value);
                    SelectedComboBoxSubjectId = -1;
                }
            }
        }
        public int SelectedListBoxSubjectId
        {
            get => _selectedListBoxSubjectId;
            set
            {
                this.RaiseAndSetIfChanged(ref _selectedListBoxSubjectId, value);
                if (value != -1)
                {
                    _unselectedSubjects.Add(_selectedSubjects[value]);
                    _selectedSubjects.RemoveAt(value);
                    SelectedListBoxSubjectId = -1;
                }
            }
        }

        public ObservableCollection<Subject> UnselectedSubjects
        {
            get => _unselectedSubjects;
            set => this.RaiseAndSetIfChanged(ref _unselectedSubjects, value);
        }
        public ObservableCollection<Subject> SelectedSubjects
        {
            get => _selectedSubjects;
            set => this.RaiseAndSetIfChanged(ref _selectedSubjects, value);
        }

        public ReactiveCommand<string, Unit> AddNewTeacherCommand { get; }
        public ReactiveCommand<string, Unit> CancelAddNewTeacherCommand { get; }


        private Teacher _teacher = new Teacher() {TeacherSurname = "", TeacherName="", TeacherPatronymic="", TeacherEmail="", TeacherPhoneNumber=""};

        private DateTimeOffset _date = DateTimeOffset.Now;

        private int _genderComboboxId = 0;
        private string _teacherWorkTime = "0";
        private int _selectedComboBoxSubjectId = -1;
        private int _selectedListBoxSubjectId = -1;

        private ObservableCollection<Subject> _unselectedSubjects = new ObservableCollection<Subject>();
        private ObservableCollection<Subject> _selectedSubjects = new ObservableCollection<Subject>();


        private void AddNewTeacherCommandRun(string param)
        {
            if (Teacher.TeacherSurname.Length == 0 || Teacher.TeacherName.Length == 0 || Teacher.TeacherPatronymic.Length == 0)
            {
                MessageBoxManager.GetMessageBoxStandard("Внимание!", "ФИО не заполненно!", MsBox.Avalonia.Enums.ButtonEnum.Ok).ShowAsync();
                return;
            }
            if (Date > DateTimeOffset.Now)
            {
                MessageBoxManager.GetMessageBoxStandard("Внимание!", "Дата ещё не наступила!", MsBox.Avalonia.Enums.ButtonEnum.Ok).ShowAsync();
                return;
            }
            if (!Regex.IsMatch(Teacher.TeacherEmail, "^[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?$"))
            {
                MessageBoxManager.GetMessageBoxStandard("Внимание!", "Email некорректен", MsBox.Avalonia.Enums.ButtonEnum.Ok).ShowAsync();
                return;
            }
            if (SelectedSubjects.Count == 0)
            {
                MessageBoxManager.GetMessageBoxStandard("Внимание!", "Преподаватель не ведёт предметов!", MsBox.Avalonia.Enums.ButtonEnum.Ok).ShowAsync();
                return;
            }
            int TeacherWorkTimeInt;
            try
            {
                TeacherWorkTimeInt = Convert.ToInt32(TeacherWorkTime);
            }
            catch
            {
                MessageBoxManager.GetMessageBoxStandard("Внимание!", "Стаж не является числом!", MsBox.Avalonia.Enums.ButtonEnum.Ok).ShowAsync();
                TeacherWorkTime = "0";
                return;
            }

            using (AvaloniaPrakt12DbContext DB = new())
            {
                List<TeachersSubject> list = new();
                foreach (var item in SelectedSubjects)
                {
                    list.Add(new TeachersSubject()
                    {
                        IdSubject = item.IdSubjects
                    });
                }
                DB.Teachers.Add(new Teacher()
                {
                    TeacherSurname = Teacher.TeacherSurname,
                    TeacherName = Teacher.TeacherName,
                    TeacherEmail = Teacher.TeacherEmail,
                    TeacherPatronymic = Teacher.TeacherPatronymic,
                    TeacherPhoneNumber = Teacher.TeacherPhoneNumber,
                    IdGender = GenderComboboxId + 1,
                    TeacherWorkTime = TeacherWorkTimeInt,
                    TeacherBirthdate = DateOnly.FromDateTime((Date.Date)),
                    TeachersSubjects = list
                });
                DB.SaveChanges();
                MessageBoxManager.GetMessageBoxStandard("Успех!", "Преподаватель добавлен в базу!", MsBox.Avalonia.Enums.ButtonEnum.Ok).ShowAsync();
            }
        }

        private void CancelAddNewTeacherCommandRun(string param) => AddNewTeacherPageWasClosed();
    }
}